This invention is related to the field of compositions that can be used to polymerize monomers into at least one polymer.
The production of polymers is a multi-billion dollar business. This business produces billions of pounds of polymers each year. Millions of dollars have been spent on developing technologies that can add value to this business.
One of these technologies is called metallocene catalyst technology. Metallocene catalysts have been known since about 1960, however, their low productivity did not allow them to be commercialized. About 1975, it was discovered that contacting one part water with two parts trimethylaluminum to form methyl aluminoxane, and then contacting such methyl aluminoxane with a metallocene compound, formed a metallocene catalyst that had greater activity. However, it was soon realized that large amounts of expensive methyl aluminoxane were needed to form an active metallocene catalyst. This has been a significant impediment to the commercialization of metallocene catalysts.
Borate compounds have been use in place of large amounts of methyl aluminoxane. However, this is not satisfactory, since borate compounds are very sensitive to poisons and decomposition, and can also be very expensive.
It should also be noted that having a heterogeneous catalyst is important. This is because heterogeneous catalysts are required for most modern commercial polymerization processes. Furthermore, heterogeneous catalysts can lead to the formation of substantially uniform polymer particles that have a high bulk density. These types of substantially uniformed particles are desirable because they improve the efficiency of polymer production and transportation. Efforts have been made to produce heterogeneous metallocene catalysts, however, these catalysts have not been entirely satisfactory.
Therefore, the inventors provide this invention to solve these problems.
An object of this invention is to provide a process that produces a composition that can be used to polymerize monomers into at least one polymer.
Another object of this invention is to provide said composition.
Another object of this invention is to provide a process to polymerize monomers into at least one polymer using said composition.
Another object of this invention is to provide a manufacture that comprises at least one said polymer.
Another object of this invention is to provide a machine that comprises at least one said manufacture.
In accordance with one embodiment of this invention, a process to produce a composition of matter is provided. Said process comprises (or optionally, consists essentially of, or consists of) contacting an organometal compound, a solid Lewis acid compound, and an organoaluminum compound to produce said composition, wherein said composition consists essentially of (or optionally, consists of) a post-contacted organometal compound, a post-contacted solid Lewis acid compound, and optionally, a post-contacted organoaluminum compound.
In accordance with another embodiment of this invention, a composition of matter is provided. Said composition consists essentially of a post-contacted organometal compound, a post-contacted solid Lewis acid compound, and optionally, a post-contacted organoaluminum compound.
In accordance with another embodiment of this invention, a process to polymerize monomers into at least one polymer using said composition is provided. Said process comprises contacting said composition with monomers.
In accordance with another embodiment of this invention a manufacture is provided. Said manufacture comprises at least one said polymer.
In accordance with another embodiment of this invention a machine is provided. Said machine comprises at least two said manufactures.
These objects, and other objects, will become more apparent to those with ordinary skill in the art, by reading this disclosure.
It should be noted that the phrase xe2x80x9cconsisting essentially ofxe2x80x9d means that the only other items (such as, for example, process steps, and other compounds) included within the scope of the claims are those items that do not materially affect the basic and novel characteristics of the claimed invention.
It should also be noted that the phrase xe2x80x9cconsisting ofxe2x80x9d means that the no other items (such as, for example, process steps, and other compounds) are included within the scope of the claims, except items that are impurities ordinarily associated with a composition, or items that are process steps ordinarily associated with a process.
Organometal compounds used in this invention have the following general formula.
(X1)(X2)(X3)(X4)M1xe2x80x83xe2x80x83FORMULA ONE:
In this formula, M1 is selected from the group consisting of titanium, zirconium, and hafnium. Currently, it is most preferred when M1 is zirconium.
In this formula (X1) is independently selected from the group consisting of (hereafter xe2x80x9cGroup OMC-Ixe2x80x9d) cyclopentadienyls, indenyls, fluorenyls, substituted cyclopentadienyls, substituted indenyls, such as, for example, tetrahydroindenyls, and substituted fluorenyls, such as, for example, octahydrofluorenyls.
The substituents on the substituted cyclopentadienyls, substituted indenyls, and substituted fluorenyls, can be aliphatic groups, cyclic groups, combinations of aliphatic and cyclic groups, and organometallic groups, as long as these groups do not substantially, and adversely, affect the polymerization activity of the composition. Additionally, hydrogen can be a substituent.
Suitable examples of aliphatic groups are hydrocarbyls, such as, for example, paraffins and olefins. Suitable examples of cyclic groups are cycloparaffins, cycloolefins, cycloacetylenes, and arenes. Additionally, alkylsilyl groups where each alkyl contains 1-12 carbon atoms, alkyl halide groups where each alkyl contains 1-12 carbon atoms, or halides, can also be used.
Suitable examples of such substituents are methyl, ethyl, propyl, butyl, tert-butyl, isobutyl, amyl, isoamyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, dodecyl, 2-ethylhexyl, pentenyl, butenyl, phenyl, chloro, bromo, and iodo.
In this formula (X3) and (X4) are independently selected from the group consisting of (hereafter xe2x80x9cGroup OMC-IIxe2x80x9d) halides, aliphatic groups, cyclic groups, combinations of aliphatic and cyclic groups, and organometallic groups, as long as these groups do not substantially, and adversely, affect the polymerization activity of the composition.
Suitable examples of aliphatic groups are hydrocarbyls, such as, for example, paraffins and olefins. Suitable examples of cyclic groups are cycloparaffins, cycloolefins, cycloacetylenes, and arenes. Currently, it is preferred when (X3) and (X4) are selected from the group consisting of halides and hydrocarbyls, where such hydrocarbyls have from 1 to 10 carbon atoms. However, it is most preferred when (X3) and (X4) are selected from the group consisting of fluoro, chloro, and methyl.
In this formula, (X2) can be selected from either Group OMC-I or Group OMC-II.
When (X2) is selected from Group OMC-I, it should be noted that (X1) and (X2) can be joined with a bridging group, such as, for example, aliphatic bridging groups, cyclic bridging groups, combinations of aliphatic and cyclic bridging groups, and organometallic bridging groups, as long as the bridging group does not substantially, and adversely, affect the polymerization activity of the composition.
Suitable examples of aliphatic bridging groups are hydrocarbyls, such as, for example, paraffins and olefins. Suitable examples of cyclic bridging groups are cycloparaffins, cycloolefins, cycloacetylenes, and arenes. Additionally, it should be noted that silicon and germanium are also good bridging units.
Various processes are known to make these compositions. See, for example, U.S. Pat. Nos. 4,939,217; 5,210,352; 5,436,305; 5,401,817; 5,631,335, 5,571,880; 5,191,132; 5,480,848; 5,399,636; 5,565,592; 5,347,026; 5,594,078; 5,498,581; 5,496,781; 5,563,284; 5,554,795; 5,420,320; 5,451,649; 5,541,272; 5,705,478; 5,631,203; 5,654,454; 5,705,579; and 5,668,230; the entire disclosures of which are hereby incorporated by reference.
Specific examples of such compositions are as follows:
bis(cyclopentadienyl) hafnium dichloride;
bis(cyclopentadienyl) zirconium dichloride;
[ethyl(indenyl)2] hafnium dichloride;
[ethyl(indenyl)2] zirconium dichloride;
[ethyl(tetrahydroindenyl)2] hafnium dichloride;
[ethyl(tetrahydroindenyl)2] zirconium dichloride;
bis(n-butylcyclopentadienyl) hafnium dichloride;
bis(n-butylcyclopentadienyl) zirconium dichloride;
((dimethyl)(diindenyl) silane) zirconium dichloride;
((dimethyl)(diindenyl) silane) hafnium dichloride:
((dimethyl)(ditetrahydroindenyl ) silane ) zirconium dichloride;
((dimethyl)(di(2-methyl indenyl)) silane) zirconium dichloride; and
bis(fluorenyl) zirconium dichloride.
Organoaluminum compounds have the following general formula.
xe2x80x83Al(X5)n(X6)3-nxe2x80x83xe2x80x83FORMULA TWO:
In this formula (X5) is a hydrocarbyl having from 1-20 carbon atoms. Currently, it is preferred when (X5) is an alkyl having from 1 to 10 carbon atoms. However, it is most preferred when (X5) is selected from the group consisting of methyl, ethyl, propyl, butyl, and isobutyl.
In this formula (X6) is a halide, hydride, or alkoxide. Currently, it is preferred when (X6) is independently selected from the group consisting of fluoro and chloro. However, it is most preferred when (X6) is chloro.
In this formula xe2x80x9cnxe2x80x9d is a number from 1 to 3 inclusive. However, it is preferred when xe2x80x9cnxe2x80x9d is 3.
Examples of such compounds are as follows:
trimethylaluminum;
triethylaluminum;
tripropylaluminum;
diethylaluminum ethoxide;
tributylaluminum;
triisobutylaluminum hydride;
triisobutylaluminum; and
diethylaluminum chloride.
Currently, triethylaluminum is preferred.
Solid Lewis acid compounds are compounds that have Lewis acidity. It is preferred when said solid Lewis acid compounds comprise solid mixed oxides. It is also preferred when said solid mixed oxide compounds comprise oxygen and at least two elements selected from the group consisting of groups 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15 of the periodic table, including lanthanides and actinides (See Hawley""s Condense Chemical Dictionary, 11th Edition). However, it is preferred when the elements are selected from the group consisting of Al, B, Be, Bi, Cd, Co, Cr, Cu, Fe, Ga, La, Mn, Mo, Ni, Sb, Si, Sn, Sr, Th, Ti, V, W, P, Y, Zn and Zr. It is important that these solid mixed oxide compounds have electron withdrawing ability, while not wanting to be bound by theory, it is believed that solid mixed oxide compounds should have high Lewis acidity. However, it is hard to accurately measure the Lewis acidity of these solid mixed oxide compounds, or other solid Lewis acid compounds, so other methods have been used. Currently, comparing the activities of solid mixed oxide compounds, or solid Lewis acid compounds, under acid catalyzed reactions is preferred.
Suitable examples of solid mixed oxide compounds include, but are not limited to, mixtures of Al2O3, B2O3, BeO, Bi2O3, CdO, Co3O4, Cr2O3, CuO, Fe2O3, Ga2O3, La2O3, Mn2O3, MoO3, NiO, P2O5,Sb2O5, SiO2, SrO, ThO2, TiO2, V2O5, WO3, Y2O3, ZnO, and ZrO2. Currently, a solid mixed oxide compound containing three or more elements is preferred. One preferred solid mixed oxide compound comprises a mixed oxide that has oxygen bonded to Zr, B, and Al. Additionally, it should be noted that solid mixed oxide compounds that comprise Al-O and two other element-oxygen bonds are currently preferred.
It is important that the solid mixed oxide compound is calcined. This calcining can be conducted in an ambient atmosphere, preferably a dry ambient atmosphere, at a temperature in the range of about 300xc2x0 C. to about 900xc2x0 C., and for a time in the range of about I minute to about 100 hours. Currently, temperatures from about 500xc2x0 C. to about 700xc2x0 C. and a time in the range of about 1 hour to about 10 hours, are preferred.
Solid mixed oxide compounds, should have pore volumes greater than about 0.01 cc/g, preferably greater than about 0.1 cc/g, and most preferably, greater than about 1 cc/g.
Solid Lewis acid compounds should have surface areas greater that about 1 m2/g, preferably greater than 100 m2/g, and most preferably greater than 200 m2/g.
Solid mixed oxide compounds should have surface areas greater that about 1 m2/g, preferably greater than 100 m2/g, and most preferably greater than 200 m2/g.
Solid mixed oxide compounds can be produced in a variety of ways, such as, for example, co-gelling, or impregnation of one compound onto another.
The compositions of this invention can be produced by contacting an organometal compound, a solid Lewis acid compound, preferably a solid mixed oxide compound, and an organoaluminum compound, together. This contacting can occur in a variety of ways, such as, for example, blending. Furthermore, each of these compounds can be fed into the reactor separately, or various combinations of these compounds can be contacted together before being further contacted in the reactor, or all three compounds can be contacted together before being introduced into the reactor. Currently, one method is to first contact the organometal compound and the solid Lewis acid compound together, for about 1 minute to about 24 hours, preferably, about 1 minute to about 1 hour, at a temperature from about 10xc2x0 C. to about 200xc2x0 C., preferably about 25xc2x0 C. to about 100xc2x0 C., to form a first mixture, and then contact this first mixture with an organoaluminum compound to form the composition.
During contacting, or after contacting, the mixtures or the composition can be calcined. This calcining can be conducted in an ambient atmosphere, preferably a dry ambient atmosphere, at a temperature in the range of about 300xc2x0 C. to about 900xc2x0 C., and for a time in the range of about 1 minute to about 100 hours. Currently, temperatures from about 500xc2x0 C. to about 700xc2x0 C. and a time in the range of about 1 hour to about 10 hours, are preferred.
After contacting, the composition consists essentially of, (or consists of) a post-contacted organometal compound, a post-contacted solid Lewis acid compound, and optionally, a post-contacted organoaluminum compound. It should be noted that the post-contacted solid Lewis acid compound is the majority, by weight, of the composition. Since the exact order of contacting is not known, it is believed that this terminology best describes the composition""s components.
The composition of this invention has an activity greater than a compound that uses the same organometal compound, and the same organoaluminum compound, but uses untreated Ketjen grade B alumina (see comparative examples 4, 5, and 6) instead of the solid Lewis acid compounds of this invention. This activity is measured under slurry polymerization conditions, using isobutane as the diluent, and with a polymerization temperature in the range of 50 to 150xc2x0 C., and an ethylene pressure of in the range of 400 to 800 psig. However, it is preferred if the activity is greater than 100 grams polyethylene per gram of solid Lewis acid compound per hour (hereafter xe2x80x9cgP/(gSxc2x7hr)xe2x80x9d), more preferably greater than 150, even more preferably greater than 200, even more preferably greater than 250, and most preferably greater than 300. This activity is measured under slurry polymerization conditions, using isobutane as the diluent, and with a polymerization temperature in the range of 90xc2x0 C., and an ethylene pressure of in the range of 550 psig. The reactor should have substantially no indication of any wall scale, coating or other forms of fouling.
These compositions are often sensitive to hydrogen and sometimes incorporate comonomers well, and usually produce polymers with a low HLMI/MI ratio.
One of the important aspects of this invention is that no aluminoxane needs to be used in order to form the composition. This also means that no water is needed to help form such aluminoxanes. This is beneficial because water can sometimes kill a polymerization process. Additionally, it should be noted that no borate compounds need to be used in order to form the composition. In summary, this means that the composition, which is heterogenous, and which can be used for polymerizing monomers, can be easily and inexpensively produced because of the substantial absence of any aluminooxane compounds or borate compounds. Additionally, no organochromium needs to be added, nor any MgCl2 needs to be added to form the invention.
The monomers useful in this invention, are unsaturated hydrocarbons having from 2 to 20 carbon atoms. Currently, it is preferred when the monomer is selected from the group consisting of ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 3-methyl-1-pentene,4-methyl-1-hexene, 3-ethyl-1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and mixtures thereof However, when a homopolymer is desired, it is most preferred to use ethylene, or propylene, as the monomer. Additionally, when a copolymer is desired, it is most preferred to use ethylene and hexene as the monomers.
Processes that can polymerize monomers into polymers are known in the art, such as, for example, slurry polymerization, gas phase polymerization, and solution polymerization. It is preferred to perform a slurry polymerization in a loop reactor. Furthermore, it is even more preferred to use isobutane as the diluent in a slurry polymerization. Examples of such technology can be found in U.S. Pat. Nos. 4,424,341; 4,501,885; 4,613,484; 4,737,280; and 5,597,892; the entire disclosures of which are hereby incorporated by reference.
It should be noted that under slurry polymerization conditions these compositions polymerize ethylene alone, or ethylene with a 1-olefin, or propylene very well. In particular, the compositions used in this process